A common or electrical bus is used in a variety of applications including work machines, vehicles and computers. Electrical buses may also be used in high voltage applications to deliver power from a power source to the electrical devices. An electrical bus is essentially a parallel circuit that is used to connect a plurality of electrical devices together with power sources, such as generators, solar cells, batteries, and the like. Moreover, electrical buses may be used in direct current (DC) applications and have a positive line and a negative line, or ground line, over which a potential voltage difference may be provided.
A problem that may arise in DC voltage applications is that electrical devices may store electrical power. Consequently, when the electrical bus is disconnected from a power source, the electrical devices continue to energize the electrical bus with the stored electrical power. Thus, a relatively long period of time may be required for the electrical bus to return to a low energy state where the electrical potential difference between the positive line and the negative line is minimal. As technicians are forced to wait for the electrical bus to return to a low energy state before beginning repairs, the total time required to repair and maintain such machines as well as the costs associated therewith are compounded dramatically.
Many currently existing high voltage electrical buses employ a bleeder resistor to help dissipate the stored energy once the associated power supply is shut off or disconnected. For example, U.S. Patent Application No. 2009/0141412 to Hickam discloses a discharge circuit having a power resistor that is connected across the positive and negative lines of the associated electrical bus for discharging current flow therethrough. While such bleeder resistors provide some degree of energy dissipation, the rate of discharge is still limited to a natural rate of decay which still requires a substantial wait time especially for high voltage applications. Furthermore, such discharge circuits and bleeder resistors are susceptible to failure, which may pose a significant safety risk in devices that are not equipped with secondary safeguards as a fallback.
The disclosed system and method is directed at overcoming one or more of the problems set forth above.